1. Field of the Invention
The present invention relates to a method of forming a lug or stop protrusion or a seat on a shaft of substantially uniform diameter by a vertical pressing action. A specifically useful applicability is for use in making a pedal rod used in the automotive industry.
2. The Prior Art
A pedal rod is typically used with a vehicular pedal to respond to pressure applied by the foot of an operator, thereby to actuate a mechanical device. For example, when pressure is applied to a brake pedal, a valve body is urged into a vacuum chamber which in turn actuates a piston of a master cylinder containing liquid which actuates the pistons of wheel brakes.
The shaft of most pedal rods typically includes a ring-shaped stop for seating and/or retaining a spring. The stop is located along the shaft at a fixed and predetermined location. The shaft of the pedal rod can be various diameters, but typically a one-half inch diameter or three-eighths inch diameter rod is used.
To form a stop on such prior art pedal rods, if a one-half inch diameter rod is used, a cold header operation may be required to produce a ring by using horizontal pressure to form the ring.
In other forms of prior art, a groove is cut in the surface of the rod in order to receive and seat a snap ring.
In addition, a slow chucking operation is required before entering the forging process, if any kind of machining is contemplated. Such operations are both costly and time consuming. The cost of materials, in addition, is significantly greater since one-half inch diameter rods are usually required to be used to implement the prior art forming methods.
Most pedal rods have a ball component of a ball joint on one end which must be formed by machining to achieve the required precision sizing. Unless the diameter of the ball joint permits, any attempt to introduce a stop forming action in an axial direction past the ball joint will fail.
The prior art is exemplified by my prior U.S. Pat. No. 4,901,426.